Just implemented a pricey Sherco spark arrestor solution, the 1.25" aluminum weldment adapter and 32mm machined aluminum Sparky on a customer bike. I say 'pricey' because both bought together aren't cheap. If you need a spark arrestor for a Sherco-Scorpa, the compound angle of the muffler end makes adapting a spark arrestor without a custom adapter difficult. Got both from RYP. The adapter does not fit into the muffler exit hole but lines up with it. Flow is thus not resisted much, so the negative influence on jetting is minimized. The 32mm Sparky is 0.01" oversize on the adapter, whereas the adapter is sourced from tubing extruded to inch nominal outside diameter. The fit is quite sloppy, with the clamp screw distorting the clamp to get to a point of retention. My fix was to cut some 0.008" aluminum flashing to lay fit between adapter shaft and Sparky bore. The fit becomes right when a single cut piece covers about 35% of the area. The clamp screw then easily retains the spark arrestor. The adapter doesn't fit quite flush on the muffler end because the muffler has a slight angled projection round the exit tube. I used a stainless washer under the adapter flange at the bottom screw to shim the gap to provide better support. I also sealed the adapter to the plastic with clear Silicone 1 rubber, which is good to 500 degrees. I hope I like the sound on my 250 with the Sparky off, so I can just leave an adapter on. I plan to machine my own adapter to 32mm. It will include the flange so there won't be a weld on mine. Mine also won't need shimming. But I'll mount it like the weldment with two screws. The weldment adapter screws on with two small countersunk-head, stainless-steel Phillips screws. I lined it up with the muffler hole and muffler facets, then drilled two 0.085" holes, which allowed the screws to form full threads. I prefer to safety wire mine so it vibrated or knocked off in a crash the items will dangle instead of disappear into another universe. I use some Malin Co. 0.025" stainless steel wire looped through the Sparky clamp screw slot and affixed to the top inside muffler tip screw. My previous solution was my own adapter with a Sparky. It was more restrictive, however, being on a tube that fit inside the muffler exit hole instead of lining up with the hole. Please show us your solutions!